Participation in this study is limited to patients with X-linked adrenoleukodystrophy who have evidence of a brain inflammatory response on the basis of gadolinium magnetic resonance imaging studies, and whose neurologic involvement is too advanced for consideration of bone marrow transplant. The double blinded placebo-controlled study aims to determine whether progression of the inflammatory cascade can be interrupted by beta interferon or by thalidomide. Twenty-one patients have been enrolled in this demanding protocol and are evaluated by highly quantitative measures including a newly developed volumetric magnetic resonance image analysis. Except for skin rashes in two patients no signnificant side effects have been observed. While the majority of the patients with this extremely grave form of ALD have continued to lose gound neurologically, the data suggest that some of the patients have stabilized. The code has not been broken. The study is being monitored by an unblinded data management and monitoring committee. The committee has advised us that no statistically significant differences have emerged between the three groups with the limited data available at this time and has advised us to continue the study. We anticipate to enroll an additional 20 patients during the next year.